Wound retractors in the form of a fixed diameter (up to 11 mm) solid (nonsplit) tube are widely known to be used for cholecystostomy, gastrostomy, appendectomy, and in gynecological surgery. However, a fixed diameter of the heretofore-known wound retractors interferes with or renders some manipulations impracticable altogether. Thus, for instance, laparoscophic appendectomy involves the introduction of four wound retractors into patient's abdominal cavity, each of them being a fixed-diameter solid tube through which the stages of the appendectomy procedure are carried out with the aid of appropriate instruments (cf.`Endoscopy`, v.15, No. 2, March 1983, New York, K. Semm, `Endoscopy Appendectomy`, pp. 59-64).
Another prior-art wound retractor is known to comprise a split tube made up of two halves, holders of the tube halves, and a mechanism for spreading the tube halves apart, provided with a retainer for the tube halves to lock in position (cf. Waldemar Link, Rectum- und Abdominal-Chirurgie, 1984, FIG. 20-1440).
In the known wound retractor the holders of the tube halves are shaped as curved rods held with their ends to the respective tube half so as to provide a possibility of turning the tube half about an axis passing through the point of rod-to-tube half holding. The mechanism for spreading the tube halves apart is in fact a micrometer screw interposed between the vacant ends of the holders of the tube halves.
The heretofore-known wound retractor suffers from an inadequately rigid construction which makes it impracticable for a majority of surgical procedures, such as, e.g., laparoscopic appendectomy.
Application of the heretofore-known wound retractor is fraught with cocking of the tube halves with respect to each other, which precludes introduction of surgical instruments through it and might result in expelling of the tube out of the wound. Besides, the holders might be bent with respect to the holding place of the mechanism for the tube halves spreading apart, which leads to departure from a preset distance between the set-apart tube halves, and affects adversely the reliability of holding the wound lips in place.